Saint assaulted the 55-year-old 109 bus driver on September 15, 2013, after he held the bus temporarily outside Thornton Heath Bus Garage while the drivers changed.

Saint, a passenger, approached the driver as he was getting out of his cab and demanded he move the bus before punching the victim on the hand.

Saint then made off after the new driver boarded the bus to take over and intervened.

He was found guilty of common assault and section 5 public order after a trial on Friday, March 28.

The conviction was the result of an investigation by the Met's Safer Transport Command (STC) which is funded by Transport for London.

Chief Superintendent Sultan Taylor, from the STC said: "This unprovoked attack on a bus driver has resulted in the offender being given a significant prison sentence, thanks to the investigation by our Workplace Violence Unit.

"This type of behaviour on London's bus network will not be tolerated."

And Steve Burton, TfL's Director of Enforcement and On-Street Operations, said: "This was a mindless, unprovoked attack towards our bus driver who was just doing his job.

"Our staff should be allowed to carry out their daily work duties without fear of attack from the travelling public.

"Thanks to the work and efforts of the Safer Transport Command this offender has been successfully prosecuted and jailed.

"We will continue to work with our policing partners to identify offenders and push for the toughest penalties for anyone who abuses our staff."